In recent years, deaths have been reported that are caused by infections with new types of viruses such as SARS (severe acute respiratory syndrome) and avian influenza. At present, because of developments in transportation and mutations of viruses, the world faces the risk of a “pandemic” that is an epidemic of viral infection throughout the world, and there is an urgent need for countermeasures. To deal with such a situation, the development of vaccine-based antiviral drugs is hastened. However, since vaccines have their own specificity, they can only prevent infection with specific viruses. Moreover, preparation of vaccines for the new types of viruses needs a considerable amount of time.
To prevent infection with such viruses, it is recommended to wear a mask. However, the problem with wearing a mask is that secondary infection may occur because viruses adhering to the used mask may adhere to hands when the mask is disposed of. Therefore, a mask is of little use in preventing infection perfectly.
To solve the foregoing problem, masks having the effect of inactivating viruses (reducing the infectivity of the viruses or deactivating the viruses) have been proposed (for example, Patent Literatures 1 and 2). Patent Literature 1 proposes a mask having the effect of inactivating bacteria and viruses. More specifically, iodine is adsorbed on anion exchange fibers prepared by bonding ion exchangeable functional groups such as amino groups to the fiber matrix, and a cloth containing the iodine-adsorbed fibers is used for the body of the mask. In a mask in Patent Literature 2, a cloth supporting a component extracted from Sasa veitchii and an inorganic porous material is used for the body of the mask to impart the effect of inactivating viruses to the mask.